I fired about 20, IIRC, from my new Strike without issue. Its plug is much simpler than the one for my Knight. That one has three different inside diameters to deal with, plus the wire-sized bit. If you let it get crudded up, it's a job to clean, and that crud is hard!
Couldn't you just pull the breech plug and soak it in brake cleaner to soften the crud?
